Ethylene plastics such as polyethylene and an ethylene/vinyl acetate copolymer can be easily formed by various methods. Especially, in the field of wrapping films, they have been used in great quantities, because of their chemical resistance, transparency, heat sealability, etc.
Recently the use of wrapping films has been diversified. Under these circumstances, there has been a growing demand for a film having specific properties reverse to inherent properties of polyethylene. There have been preferably used most of polyethylene films having surface smoothness, reflective gloss, good transparency, and relatively high stiffness. In the field of specific wrapping films such as a wrapping film for sanitary goods, and also in the field of specific goods such as throwaway rainwears and medical sheets, there has been a demand for a film having properties reverse to those of a conventional polyethylene film, namely, a film which has no reflective gloss, opacity, soft and smooth touch, and which sounds low when it is crumpled.
It has been said difficult to manufacture such a film as having the above specific properties using conventional processing technique or a polyethylene resin. There is known a silk-like polyethylene plastic film made of a mixture comprising an ethylene/vinyl acetate copolymer and polyethylene, for example, as disclosed in JP-A No. 61-106645 (The term "JP-A" as used herein means an "unexamined published Japanese patent application"). However, this published application has problems that when a film processing machine once stops and then starts, it takes a long time for a cleanup operation so that much resins will be discarded until good extruded products are obtained Further, it is substantially impossible to process said mixture because the ethylene/vinyl acetate copolymer is thermally decomposed at a processing temperature of 240.degree. C. or more.
There are known formed products made of a mixture comprising polyethylene and a copolymer of ethylene and a vinyl ester (e.g., vinyl acetate); or a mixture comprising polyethylene and a copolymer of ethylene and an ester of an unsaturated carboxylic acid (e.g., methyl acrylate, ethyl acrylate), for example, as disclosed in JP-A No. 50-10838 and JP-B No. 40-24913 (the term "JP-B" as used herein means an "examined Japanese patent publication"). The object of these publications is to improve the stress cracking resistance and high-impact properties of the formed products, thus they are different from this invention in object.